yeah, I found an existing chat and responded. I waited a minute and didn't see a reply so I moved on. Maybe I'm just impatient. If the intent is for not all chats to be realtime, maybe something to remind folks to check back may help until you hit critical mass. If not, maybe some kind of indication that the other party is present and waiting for a response.
It would also be nice to be able to easily leave a conversation so it doesn't fill up the 'my conversations' window. The conversation could then go back to the main list to be fulfilled by someone else maybe.
Aha. Maybe a flag both on the index page and in the chat window that a user is offline? And an option to leave a conversation even if a responder wrote messages but didn't get any from an author yet? Then this conversation goes back to the index page.
Yeah that'd be cool. There could be other circumstances where you'd want to be able to leave a conversation as well-- abusive, bad partner, etc. Anyway again- nice work.